73k5blazerUnplug the matrix cable from the back of your headPremium Member

I'm picking some parts for my Daily driver SBC rebuild, and have come down to valve springs. The cam I want comes in two different kits,
1 kit has cam, timing chain/sprockets, lifters and another kit has
cam, timing chain/sprockets,lifters, valve springs/locks/retainers/seals''

The second kit is like $70 more that the first, and if I don't get them in that kit, the master engine kit that has new springs and stuff is like $30 more.

So what's really in a valve spring? What would comp cams spring have over the no-name stocker?

Different springrates , just like leaf springs . Just like a heavier truck needs stiffer springs , different cams need different weight springs . Stock valvesprings are only good to a certain amount of lift .

Dunno if it's required or not, but when I had my (Vortec) heads at the machine shop, the springs are checked to make sure that the pressure is consistent, and they are shimmed if necessary to get them all to within whatever tolerance is necessary.

Curious to hear what others know about valve springs and checking pressure as installed on them in a "normal" application.

That service is included when they install springs at the shop I took them to. I may not have taken the heads there at all except I thought they would have to be machined. Turns out the shop had some heavier springs that they took the inner coils out of that came in at exactly the right pressure recommended for the cam, and ended up being cheaper than buying the springs somewhere else to boot!

73k5blazerUnplug the matrix cable from the back of your headPremium Member

Taking alot of this information and digging around a little more, it seems the stock springs are sufficient for the cam I plan on running. Provided of course mine meet stock specification, which has yet to be determined, but if they don't I'll get new ones.
What about retainers, locks and seals? Never built heads before (exchanged them, buy never built). Do the retainers need installed by the machine shop, or can the average joe do that?
Thanks for all the excellent help!

Retainers are sized to fit a particular diameter of spring whether it be a 1.25" or 1.437" or etc.

Valve seals keep oil from running down the guide and into the chamber,
I prefer Viton seals.....Umbrella seals are the most common on a stock head but the guides must be machined for quality press fit seals.

Locks come in 2 sizes, 7 and 10 degree depending on which retainers are used and hold the assy together.

There is only so much you can do with a spring compressor,

You still need to machine the guides for quality seals and check the installed spring height......

You can buy the tools to do the work but it's more cost effective to have a machine shop do it for ya

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